


Assimilation

by SpartanM255



Category: Halo, Mass Effect, XCOM: Enemy Unknown (2012)
Genre: Action, Advancement in Technology, Cross Over, F/M, Heavy Losses, Spartans
Language: English
Status: In-Progress
Published: 2014-11-15
Updated: 2014-11-16
Packaged: 2018-02-25 13:01:24
Rating: Mature
Warnings: Graphic Depictions Of Violence, Major Character Death
Chapters: 2
Words: 2,361
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/2622716
Author URL: https://archiveofourown.org/users/SpartanM255/pseuds/SpartanM255
Summary: <blockquote class="userstuff">
              <p>The year is 2397, humanity has spread through the solar system yet to expand beyond. It is an golden age the little rebellion that occurs is quickly quelled by the UNSC navy, using the large number of warships they possessed. Security had never been an issue until the invasion began, and everything went to hell.</p>
            </blockquote>





	1. First Wave

Sirens filled the ears of everyone in the hidden asteroid's secret military research and development complex. Word of a full scale assault from an enemy unknown, reached them only a few minutes ago. According to messages they were receiving the mining facilities on Pluto had been obliterated, and the ninth fleet was getting torn apart. They even had reports Earth's defenses had been attacked, unsuccessfully, but the fact this force had made it that far was troubling.

"Attention all military personnel are required to report to the closest hangar bay for deployment immediately." repeated the base's AI, Vigilance.

"We heard you the first time!" yelled a running marine.

Hundreds of marines were running through to the hangars, strapping on helmets, and slinging weapons over their shoulders. Corporal Tucker, took a seat in the last seat in a pelican. He recognized some of the face in the drop ship. Private Maxwell, Sergeant Newhorn, Corporal Ricker, and six others he'd seen, but couldn't place. This was bad though never since he accepted this assignment had he been deployed. This was the XRRF (Xenomorphic and Rebellion Response Force), Tucker never actually expected to be sent into combat. He joined to finish out his contract with the military, the pay was great, and the equipment was more advanced, but he didn't expect to use it other than practice.

"Finally some damn action!" Newhorn puffed a cigar.

"Yeah" Maxwell replied a little shaky, "but if they are sending us then it has to be aliens right?"

"Or rebels." Ricker corrected him.

"No rebels have ever attacked Earth before." Maxwell snapped, "We are fighting aliens."

"Hell yeah!" Newhorn roared, "About damn time. Always wanted to shoot a little gray bastard."

"Where are we going anyway?" Maxwell looked around at the marines.

A Colonel looked over at him, "Mars."

The pelican docked in one of the three destroyers bays. As soon as all three were loaded they left the hangars, and exited the asteroid's stealth field, then speeded towards Mars.

The red planet was more red than it was supposed to be. A battle was taking place over one of its major cities, the city its self was burning, but still intact.

The captain yelled over all the pelican's comms "All drop ships deploy!"

The marines could hear the muffled sounds of MAC guns firing as they descended to the planet.

When their boots hit the ground they were even more disheartened. Buildings were burning, charred corpses of soldiers lay across streets, and crashed drop ships half melted were stuck in the ground. The Colonel they flew in with ordered all marines to form up, and move out, it helped to change focus from the carnage around them.

They ran down streets checking buildings for survivors, of which they found none. Newhorn shouted "Fuck you alien piece of shit!", and he fire a six round burst from his assault rifle. Every nearby marine ran over securing the area, checking for hostiles.

The Colonel approached Newhorn. "What happened Sergeant?"

"Sir." Newhorn saluted, "Got a little pay back sir." Newhorn pointed to the corpse of a small gray humanoid with an enlarged head.

"Parker!" the Colonel yelled into his mic, "We've made contact, send team to recover a body at this location over."

"Roger sir" Parker answered back, "recovery team inbound."

After that the Colonel gave the order to move out again. They all knew what they were here for, rescue any civilians, and retrieve all enemy resources possible, that meant bodies, weapons, armor, everything. The Colonel ordered a halt, and to fall in. All three hundred marines grouped up to listen to the Colonel.

"Alright marines" the Colonel began, "We got multiple hostiles ahead. Twelve of the gray ones and a hovering one. The hovering one appears cyberneticly augmented..."

"Sir!" a marine interrupted, "Civilians spotted in building directly behind enemy."

"Damn it!" the Colonel cursed, "We got to get them out! I want everyone with a shotgun move through this building, and get as close as you can; you are the assault team. Anyone with a sniper rifle get to the top floor; you're the over watch. The rest of you will be with me we will engage the enemy head on; we are the wall that will hold the enemy off while the assault rescues those civilians. Now get into positions!"

The marines moved in cover near, destroyed cars, ruined building, and wracked military vehicles. Avoiding the attention of the seemingly occupied aliens.

"Everyone green?" the Colonel radioed to all teams.

Assault team, over watch, and the main force all replied, "Good sir."

"Over watch?" the Colonel asked, "Do you have sights on the enemy?"

"Yes sir." the ranking officer reported.

"Fire at will." the Colonel ordered.

All six members of over watch picked their targets, and opened fire. Three of the gray one were hit in the chest, and died instantly, one shot hit near another, and one hit the hovering enemy with little effect. Then a second later the Colonel ordered for his group to take the rest down. Four of the gray ones were already taking cover while the other five were torn to shreds from the thousands of bullets racing through the air. The hovering one took several seconds of the oncoming fire, before its thrusters quit. It did release a few green bursts from its weapon before dying though. Two of the bolts hit harmlessly into a building, burning through the concrete like paper. The third and fourth however hit a car door a marine took cover behind. The third hit the door melting straight through, but stopping before hitting the marine. The fourth struck him unimpeded. The green bolt bored through his chest killing him instantly, no blood flowed from the hole. No medic was called because there were still four enemies active, and they finally returned fire.

Most of the marines took cover from the deadly shots released form the small aliens, but the assault team was moving to the civilians while they were distracted. Newhorn though refused to leave his fellow marine to fight without him. He broke off from the assault team unnoticed while the rest proceeded, and moved in behind the aliens. The bolts fired by the aliens tore through the main forces cover, and killed dozens. The Colonel asked for support from over watch, but the aliens weren't in their field of view. The marines managed to kill one of the four that had escaped into cover, but the others were taking apart their cover they didn't have much longer. Newhorn snuck up on one of the grays and stuck his knife through its soft head. He then fired two shots from his shotgun at close range, cutting another in half while the other turned, and fired at him. He tried to move opening up with his pistol, but the bolt grazed his side. The last gray was dead and Newhorn was burnt to his ribs on the side that was hit, but he was alive.

The Colonel ordered casualties to be counted, and wounded to be treated, while the rest move up. They came upon Newhorn holding his side, laying on the ground.

The Colonel took a knee beside him, "I ordered the assault to get the civilians."

"I reckon they are." Newhorn said through gritted teeth.

"You disobeyed a direct order boy!" the Colonel told him waving for a medic to treat him, "And you saved our asses."

"Thank you sir." Newhorn gave him a salute.

The assault team returned through the building with the civilians.

"Mission accomplished sir." the team Lieutenant reported.

"How many dead?" the Colonel asked his second.

"Thirty-four sir." a marine answered.

A transmission came in over the marine's comms, "All XRRF forces pull back, return to base."

"What!?" the Colonel yelled into the comm, "We just got here."

"Colonel!" the AI responded, "This was just the first wave! The second wave is inbound, and we can't hold it!"


	2. The Elite

"Son of a bitch!" the Colonel cursed, "Marines we have been ordered to retreat."

Murmurs of complaint rose from all the remaining marines.

"That's enough!" he silenced them, "Now one of our destroyers has been shot down so not everyone will be leaving. The rule is if you rode it in you ride it back. So everyone who came in on the UNSC Black Bear will stay with me to wait for an alternate form of extraction."

"Sir!" Tucker spoke up, "You came in on the Firebird, not the Black Bear."

"Well someone has to keep these mangy dogs in line." the Colonel scoffed, "Now everyone that didn't come in on the Black Bear get out of here! That's an order!"

"Sir" a marine stepped forward, "I rode the Black Bear, looks like I'm staying."

"Sir" another stepped up, "Same here."

Everyone present followed suit.

"Don't lie to me maggots!" the Colonel snapped at them, "Get your sorry asses to the pelicans you came in on!"

"Sir!" Newhorn was now able to stand, "We just got here."

"Colonel." Tucker joined, "We aren't going anywhere."

"You worthless bastards!" the Colonel was smiling, "I'll have you all court martialed after we're done kicking alien ass! Collect those alien weapons, and move out!"

"Sir nothing but fragments left." a marine held a piece of one up.

The Colonel cursed, and ordered they collect some fragments and proceed. In the sky they could see green glowing projectiles like they had been shot at with only much bigger. They could make out UNSC cruisers firing at something to small to make out, and most of them were on fire. The now moving group of marines passed several alien corpses, finding only fragments of their weapons like before. Several civilian corpses were burnt to a crisp in the buildings they came upon, clearly the aliens work.

"So what's your name Colonel?" Newhorn ran up beside him.

"Shouldn't you be taking it easy Sergeant?" he replied.

"A little medi-gel and I'm good." Newhorn patted his bandaged side, "Anyway someone has to tell your family when get yourself, and us killed."

The Colonel gave him a strange look, "Then we'd all be dead, and no one would be saying anything." Newhorn, shrugged, "My name's Reese, Daniel Reese."

"Wait!" Newhorn eyes opened wide, "You mean you're the guy that infiltrated a pirate destroyer alone, and disabled it before the navy blew it up."

"They don't make you Colonel of this group for nothing..." Reese got cut off from the sound of distant gun fire.

The group moved in taking positions as close to the fight as possible without getting spotted.

"Same teams as before." Reese called over the comms, "Over watch get a drone over there. And move to the highest point you can find."

The over watch leader, Major Macko, threw out a little box into the air. The box quickly unfolded, and flew high in the air, unpacked it looked like a metal bird. Reese watched his wrist projector which displayed the drone's visuals. He could see a group of marines no more than twenty firing on large alien in purple armor, and the bullets seemed to bounce of a shield around the creature. There was only one, it was smart though it used tactics, unlike the ones before. Even the weapon it used was different, the gun was firing blue bolts instead of green. The drone zoomed in on the creature. It's mouth was odd, it had no jaw, but four tendrils moved as it made sounds, each one with sharp teeth on the inside.

"Over watch take it out." Reese ordered.

Six rounds were fired, and the alien's shield flashed, and finally sparked. Two round made it through, hitting the creature in the abdomen, and chest. It immediately fired in the direction its aggressors shot from. Several blue blots hit the roof of the building over watch was in.

"Over watch!" Reese called out, "Any wounded?"

"Two dead sir." Macko responded.

"Damn it!" Reese spat, "Stay in cover, we'll handle it from here. Assault flank from the right, we will engage when you are in position."

Assault came up on the aliens right, it was taking cover behind a corner, and it seemed to be hurt. "In position sir" Lieutenant Throne radioed.

"Everyone open up!" Reese yelled standing up, and leveling his assault rifle.

The alien jumped taken by surprise, but not stunned. Rounds impacted its shield, and the alien threw a glowing blue ball at the main force right as it rolled into the building the assault team was waiting in. Throne shot first taking the things shields down. Before they could finish it though a bright white sword materialized out of nowhere, and cut through the Lieutenant's torso. The other fourteen members were unprepared for that, which gave the creature enough time to cut through six more members in just three seconds. The remaining ones fired shotguns, pistols and anything they could get to bear in time. The alien grabbed a marine by the throat, and raised him in front of him to take the incoming fire. The marine was torn in half by the guns of his own team, and only a few rounds hit the alien. It took advantage of the shock of the assault team, and cut down two more marines. Newhorn ran up behind the thing, and shot it once in the knee. The alien fell, and back handed Newhorn through a section of dry wall. The creature hobbled over to him saying something in English it spoke English!

"Filthy human!" it growled and raised it's sword.

Newhorn was only a split second quicker on the draw. He fired two shot from his shot gun at point blank range into the things hideous face, shearing off half of it. The beast fell, and the sword disappeared. Reese moved in, and medics looked over the bodies of the marines.

"Marine!" Reese walked over to one of the five remaining assault members, "What happened?"

The marine was horrified he tried to speak but failed. Reese saw Newhorn covered in purple fluid, and laying with his eyes opened wide next to the dead alien.


End file.
